package com.banyuan.utils;

import java.security.MessageDigest;
import java.util.Collection;
import java.util.Map;
import java.util.UUID;
import java.util.regex.Pattern;

public class CommonUtils
{



	// 获取随机字符串

	public static String getRandomStr() {
		UUID uuid = UUID.randomUUID();
		String s = uuid.toString().replaceAll("-", "");
		return s;
	}



	public static boolean isEmpty(String str)
	{
		return str == null || str.trim().length() == 0;
	}

	public static boolean isNull(Object obj)
	{
		return obj == null;
	}

	@SuppressWarnings("rawtypes")
	public static boolean isEmpty(Collection collection)
	{
		return collection == null || collection.size() < 1;
	}

	@SuppressWarnings("rawtypes")
	public static boolean isEmpty(Map map)
	{
		return map == null || map.size() < 1;
	}

	// 检查字符串长度，字符串为null返回true
	public static boolean isLengthEnough(String str, int length)
	{
		if (str == null)
		{
			return false;
		}
		return str.length() >= length;
	}

	public static boolean isEmail(String email)
	{
		if (email == null)
		{
			return false;
		}
		return Pattern.matches("^\\w+([-+.]\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*$", email);
	}

	public static boolean isPhone(String phoneNum)
	{
		if (phoneNum == null)
		{
			return false;
		}
		return Pattern.matches("^1(\\d{10})$", phoneNum);
	}

	// 计算一个字符串的MD5值
	public final static String calculateMD5(String s)
	{
		char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
		try
		{
			byte[] btInput = s.getBytes();
			// 获得MD5摘要算法的 MessageDigest 对象
			MessageDigest mdInst = MessageDigest.getInstance("MD5");
			// 使用指定的字节更新摘要
			mdInst.update(btInput);
			// 获得密文
			byte[] md = mdInst.digest();
			// 把密文转换成十六进制的字符串形式
			int j = md.length;
			char str[] = new char[j * 2];
			int k = 0;
			for (int i = 0; i < j; i++)
			{
				byte byte0 = md[i];
				str[k++] = hexDigits[byte0 >>> 4 & 0xf];
				str[k++] = hexDigits[byte0 & 0xf];
			}
			return new String(str);
		} catch (Exception e)
		{
			throw new RuntimeException(e);
		}
	}

	// 判断输入字符串是否是long
	public static boolean isValidLong(String str)
	{
		if(null==str)
		{
			return false;
		}
		
		try
		{
			long v = Long.parseLong(str);
			return true;
		} catch (NumberFormatException e)
		{
			return false;
		}
	}
}
